  Regarding the 1937 coaster date, in April, 2018 an unusual example of this coaster was sold on Ebay.The seller explained it was from the Master Builders Association convention in 1937. The back of the coaster was unusual because it was stamped in ink 'Absorbo Beer Pad Co., Inc.'and also stamped '2 1/2 mm-100 point', which were design specifications. It probably is a reasonable assumption that the Absorbo company brought this, and several other coaster samples offered by the Ebay seller, to the convention to stimulate sales to the beer industry. We also believe they would have brought new designs for that year, which is why we dated this coaster as 1937. (RDA) 